1. Load up Angry Birds and go to the world select screen.
2. Center the new “Big Setup” locked world on the screen.
3. Push back button on your phone all the way out of Angry Birds.
4. Load Angry Birds back up and when the “Play” button appears, hammer on it!
5. You should be inside the locked worlds stage select screen.
6. To keep it unlocked just pass the first world.